2Cellular RespirationThe process by which the mitochondria breaks down glucose to produce ATP is called cellular respiration.C6H12O O2 6CO2 + 6H2O
3Cellular RespirationWhen the body has oxygen, aerobic respiration can take place and produce 36 ATP molecules.There are 3 stages of aerobic respiration:GlycolysisCitric acid cycle (aka Krebs Cycle)Electron transport chain
4GlycolysisGlycolysis takes place in the cytoplasm of the cell.
6GlycolysisGlycolysis is the process where glucose is broken down in 2 pyruvic acid molecules. Pyruvic acid is a 3 carbon molecule.The net gain of ATP molecules in glycolysis is 2 ATP molecules.4-22
7GlycolysisFollowing glycolysis, the pyruvic acid moves into the mitochondria.
8The Citric Acid Cycle Kreb’s cycle AKAKreb’s cycleThe Kreb’s cycle takes place in the MATRIX!Pyruvic acid enters the citric acid cycle and becomes broken down. As this occurs, 2 carbon dioxide molecules are released.In addition, 2 ATP molecules are released.Electron carriers such as FAD and NAD are used to pick up energized electrons and pass them to the ETC.
10Citric Acid Cycle 2 ATP NADH + H pyruvic acid FADH2 ADP NAD CO2 FAD Electron carriersNADNADH + HpyruvicacidFADFADH2CO2FYI: Flavin adenine dinucleotide Nicotinamide adenine dinucleotide
11The Electron Transport Chain The last step of respiration is the electron transport chain or ETC.It takes place in the inner membrane space.In the presence of oxygen, the electron transport chain will produce 32 ATP molecules and water.The total of ATP molecules released from AEROBIC respiration is 36.36363636
12Electron Transport Chain Electron carriers NADH and FADH2 release the Hydrogen ions across the membrane. This creates a concentration gradient.When oxygen enters the ETC, it becomes the final electron acceptor of the Hydrogens and creates H2O.As the hydrogen ions come back across the membrane, ADP is converted into ATP.Animation:
13Electron Transport Chain Electron carriers NADH and FADH release the Hydrogen ions to proteins to cross the membrane. This creates a concentration gradient.When oxygen enters the ETC, it becomes the final electron acceptor of the Hydrogen ions and creates H2O.As the hydrogen ions come back across the membrane, ADP is converted into ATP.
16Anaerobic Respiration AKAFermentationThere are times when cells are without oxygen for a short period of time. When this happens, anaerobic respiration is taking place.In anaerobic respiration, glycolysis takes place; then followed by one of two pathways:Lactic Acid Fermentation or Alcoholic Fermentation.Total ATP molecules released = 2.
17Aerobic: presence of oxygen Anaerobic: absence of oxygen respirationAerobic
18Types of Anaerobic Respiration When our cells run out of oxygen and begin fermentation, we build up lactic acid. That lactic acid build up in the muscle makes us feel a cramp.C6H12O6 ATP + lactic acidLactic Acid Fermentation
20Types of Anaerobic Respiration Some bacteria also undergo fermentation. They release ethyl alcohol and carbon dioxide.C6H12O6 ATP + CO2 + ethyl alcoholThis process is key for the bacteria that create wine and apple juice.Alcoholic Fermentation
22Types of Anaerobic Respiration Yeast also undergo this type of fermentation when making bread.
23Comparing Photosynthesis and Respiration Glucose madeLight energy requiredATP broken down in 2nd phase of p.s.CO2 taken inO2 releasedNeeds waterTakes place in chloroplastTakes place in autotrophsGlucose broken downLight is not requiredEnergy created in ATPCO2 releasedO2 taken inWater releasedTakes place in mitochondriaTakes place in all organismsRequire use of ATP moleculesTake place in plantsNecessary to sustain all life on earth